Agriculture
Most important question of the day: What’s for lunch?
Agriculture: deliberate land modification through plant cultivation and raising animals for food or profit.
• Percentage of labor force MDC: 5% (avg.), LDC: 55%
Source URL: http://www.faculty.de.gcsu.edu/~dvess/gissues/agrlabor.jpg
Subsistence Agriculture:
food production primary for farm family consumptionExample: slash and burn
http://upload.wikimedia.org/wikipedia/commons/6/6b/Bakweri_cocoyam_farmer_from_Cameroon.jpghttp://en.wikipedia.org/wiki/Subsistence_farming
Commercial Agriculture:
• food production primarily for sale off the farm• Can Start as subsistence farming, excess sold • Can transition to pure commercial agriculture
• http://www.internationalspecialreports.com/theamericas/00/bahamas/17-2.gifhttp://www.georgetowncranberry.com/images/skipper.jpg
Agribusiness
integration of commercial agriculture into food processing, usually by corporations
Image: http://www.agribusiness-mgmt.wsu.edu/Templates/index_images/Landscape-Green_r2_c24_.jpg
Source: http://www.agribusiness-mgmt.wsu.edu/
Wet Rice Agriculture
• Generally expands to hillsides as population increases• In earthquake zones, mudslide risks increase… Also, storms.• Image: http://geographyfieldwork.com/riceterrace_small.jpg
• Information: http://geographyfieldwork.com/RiceFarm.htm
Subsistence Cash Crop
Flooding, pests, drought, wind, disease, population
(Same)
Lower yield
No / low debt
Higher yield
Need inputs
Higher debt
Low profit Profits machinery, inputs, savings for lean years
Swidden Agriculture / slash and burn / shifting cultivation
1. Slash vegetation.2. Burn the slashed veg.3. Plant in nutrient ashes. 4. Yields drop off.5. Change sites. Repeat.
Requires much land recovering from past slash and burn activities.
http://www.artsci.wustl.edu/~anthro/images/rainforest/26.JPGSlash: http://www.artsci.wustl.edu/~anthro/images/rainforest/22.JPGBurn: http://images.google.com/imgres?imgurl=http://www.artsci.wustl.edu/~anthro/images/rainforest/26.JPG&imgrefurl=http://www.artsci.wustl.edu/~anthro/images/rainforest/&h=512&w=768&sz=140&tbnid=TO1EkMcffXOxEM:&tbnh=94&tbnw=141&hl=en&start=5&prev=/images%3Fq%3Dshifting%2Bcultivation%26svnum%3D10%26hl%3Den%26lr%3D%26safe%3Doff%26client%3Dfirefox-a%26rls%3Dorg.mozilla:en-US:official_s%26sa%3DGGrowth: http://www.taa.org.uk/Courses/Week4/Swidden2.jpgTree: http://www.sln.org.uk/geography/images/SLN@Malaysia2005/Richard%20and%20Bob/Shifting%20cultivation%20266.jpgStory: http://www.artsci.wustl.edu/~anthro/images/rainforest/
Shifting cultivation (observations)• SOUND: Done wisely, it is
ecologically sound in otherwise uncultivable soils.
• POPULATION: Increasing population density eventually makes this practice unsustainable.
• TITLE: In some countries, land tenure (ownership) is established by cutting the land, not leaving it “idle” (letting it recover).
• COMPETITION: In some places, shifting cultivation is being replaced by a pattern of logging, cattle ranching, and more intensive cash crop cultivation.
• LOSS: This can be a first step in forest conversion to grassland.
http://www.artsci.wustl.edu/~anthro/images/rainforest/26.JPGhttp://www.artsci.wustl.edu/~anthro/images/rainforest/27.JPG
Issues for subsistence agriculture:• Population growth
– Forest fallow bush fallow short fallow annual multi-cropping• Intensification may not be sustainable. (Site dependent)
– New farming methods require cash.• more inputs: fertilizer, manure, new tools, more labor intensive• new seeds and new crops• Needs to have enough income to fertilize, buy equipment, buy seed.
• International trade pressure:– conversion of food crops to cash crops for more profit…– drug crops (can be involuntary)
Intensive subsistence agriculture:
Examples: wet rice cultivation, dry farming • maximize yield per acre, minimize unused land, some
double cropping• low machinery inputs, high animal and human inputs• dry farming crop rotation
Pastoral nomadism works on marginal lands…
If you avoid overgrazing!Story: http://www.geographie.uni-freiburg.de/ipg/forschung/ap1/current_projects/chad/nomads_project%20area.html
Image: http://www.geographie.uni-freiburg.de/ipg/forschung/ap1/current_projects/chad/harmattan%20vaches%20en%20transhumance%20big.jpg
MDC farming:– Mixed crop and livestock farming: crops animals humans
(e.g. beef, milk, eggs)• crop rotation, nitrogen fixing crop intermixed with primary crop(s)
– Dairy farming: within range of market (avoid spoiling), refrigeration extends this range
– Grain farming: e.g. wheat belt– Livestock ranching: often on marginal lands in the West, also
Amazonia, Pampas, Outback– Mediterranean agriculture: Horticulture: growing of fruits and
vegetables, and flowers– Commercial gardening and fruit gardening: horticulture, large
scale, migrant workers– Plantation farming: specialize in 1-2 crops, once slavery, now import
workers
How Do you figure out what to grow where?
Von Thunen Model: Important
Influences:• Market Price• Distance• Transportation Cost
– Perishability, (actually covered under transportation cost)
• Likely on the quiz, test, and final exam.
Von Thunen Model
• Distance is a function of land rent and transportation costs.• Basically, what produces the most profit at each location?• http://people.hofstra.edu/geotrans/eng/ch6en/conc6en/img/vonthunen.gif• Info: http://people.hofstra.edu/geotrans/eng/ch6en/conc6en/vonthunen.html
Issues for commercial farmers:
• Access to market: Von Thunen model (ring and transport) – Land rent and distance driven… too far no profit, lose $
• Overproduction– encourage growth of crops with global demand– price subsidies– buy surplus yield, often donate to foreign governments
• Unsustainable agriculture– move to more sustainable practices
• sensitive land management• Ridge contour tillage• limited use of chemicals• (organic farming)
Issues for subsistence farmers:
• Population growth– Forest fallow bush fallow short fallow annual
cropping multi-cropping• Conversion from slash and burn to multi-crop farming
may not be sustainable• Profit motives impact farmers.
– Lure of money– Land loss (legal, and illegal) to for-profit activity
International trade pressure:
• conversion of food crops to cash crops– may make the economy dependent on foreign
foods– if so, cash crop shortfalls or price drops
avoidable food shortages• drug crops
– forced or voluntary growth of drug crops
Strategies for increasing food supply:Increase agricultural land– marginal lands
• require careful management for long-term yields• must worry about soil salinization, selenium, etc.• desertification: human action causes land deterioration
to a desert-like state.• Increase land productivity
– green revolution• often requires nutrient inputs (external, cost)• often relies on machines (external, cost, needs gas)• seed stocks are foreign owned, possibly not self
propagating
Strategies for increasing food supply: (part 2)
Identify new sources:– Cultivate the oceans
• We are already over-fishing now. – (Stock recovery, or risk extinction.)
– Develop higher protein cereals (decrease meat demand)– Promote the consumption of under-used foods, e.g.
soybeans (soy burgers, etc.)• increase trade
– Reduces local famines– Works until you run out globally.
• Who starves first?
Food supply crises
Example: Africa• Population increases faster than local food supply.• Over-planting removes soil nutrients.• Trees harvested for firewood.• Overgrazing removes grasses and herbs.• Desertification is a major problem.
– The desert has been marching south towards the sea.• Warfare, ethnic cleansing, cash crops, and global warming
exacerbate the problem.
Questions?
• Review notes.